Mechanical pencil



Dec. 26, 19392 1.. J. MOST MECHANICAL. PENCIL Filed April 5, 1959 INVENTOR 4L -1 J49.

8, ATTORNEY Patented Dec. 26, 1939 UNiTED STATE rarest orrica 2 Claims.

My invention relates to a mechanical pencil of the type described in my pending application, Serial Number 208,739, filed May 19, 1938.

The object of the invention is to provide a simple mechanism, formed of few moving parts, for

propelling, repelling, expelling and automatically presenting a new lead to writing position.

Another object of the invention is to provide a mechanical pencil in which the lead itself is part of the feed mechanism.

A further object of the invention is to provide a feeding means which engage a portion of the lateral surface of the lead when feeding it.

In the appended drawing, forming part of this application, Figure 1 is a vertical fragmentary section of a pencil embodying my invention. The leads are removed to better illustrate the invention.

Figure 2 is an enlarged end elevation of Figure 1, with the eraser removed.

Figure 3 is an enlarged cross-section on line 3-3, Figure 1 with the lead shown in section, and

Figure 4 is an elevation of a combination gear and worm.

Referring to the drawing, III is the pencil barrel, terminating with a tip I I, having a lead outt I2. Mounted within the tip, in alignment with the opening I2, is a lead guide I3 of round tubular cross-section. The lower end of the guide is held firmly at the tip opening I2, while the upper end of said guide I3 passes through a washer I5, set firmly in the barrel at the tip. The upper end of the guide terminates with a hopper I5, positioned within the lower end of a tube I6, revolubly mounted within the barrel II]. The upper end of said tube I6 projects above the upper end of the barrel, and thereat accommodates an eraser I7. The tube It with hopper I5 therein constitutes the magazine of the barrel.

The lower end of the tube I6 bears on the washer I 4, and thereat the tube I6 is provided with teeth to form internal gear I 8. In mesh with the internal gear I8 are gears or pinions I9 revolubly mounted between the washer I4 and a washer Z0, fixed to the guide I3 below the hopper I5. The two washers housing the corresponding shafts 2| on which the spur gears I9 revolve.

The guide I3 is apertured peripherally to per- 5 mit the gears I9 to pass into the passage for the lead in the guide I3. The peripheral surfaces of the spur gears I9 are provided with spiral grooves, transforming the gears into worms, which, when engaging the lateral surface of a lead passing the 10 guide, will move it longitudinally in either direction, depending on the direction the worms are rotated through the medium of the tube III.

Although the drawing and the description refers to a pair of spur gears diametrically oppo- 5 site, three gears may be used for better engagement, or a single one may be used to advantage, particularly if a lead of angular cross-section is used in lieu of a round one described.

I claim:

1. In a mechanical pencil, a barrel having a tip forming a lead outlet, a lead guide of tubular cross-section in the tip merging with the lead outlet thereof, a hopper above the guide in the barrel, a tube revolubly mounted in the barrel 25 and housing the hopper and forming therewith a magazine for leads, an internal gear associated with the tubular member and constrained to revolve therewith, and a spur gear in mesh with the internal gear to be. revolved by said internal 30 gear, said spur gear having spiral grooves on its toothed periphery, said guide having an opening on the side thereof for admitting the spur gear into the passage substantially by the depth of its spiral grooves, to engage a lead positioned 35 in the guide.

2. In a mechanical pencil, a barrel having a lead guide, a spur gear provided with spiral grooves on its toothed periphery entering the guide from the lateral surface thereof through 40 *the depth of the spiral grooves, and means for turning the spur gear from the end of the barrel.

LUCJFER J. MOST. 

